Ion-Ion Repulsions and Charge-Shielding Effects Dominate the Permeation Mechanism through the OmpF Porin Channel

OmpF is a wide channel bacterial porin frequently employed to study selective ionic translocation. The cationic preference of this porin is mainly determined by electrostatic forces between the translocated ion and the protein and the formation of ion pairs (e.g., K+···Cl-) being previously pointed as the main cause to favor the cationic transport through the constriction zone. Hybrid quantum mechanics/molecular mechanics-molecular dynamics simulations, which have provided polarization-containing potentials of mean force profiles for different permeation scenarios, reveal significant new insights related with the ion translocation mechanism. Results show that the permeation is dominated by electrostatic interactions, which in turn affect ion-protein interactions at the constriction zone. However, it is observed that ion flow is favored by ion-ion repulsions and, in a lesser extent, by charge-shielding effects, instead of the previously pointed ionic pair formation.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:123

Enthalten in:

The journal of physical chemistry. B - 123(2019), 1 vom: 10. Jan., Seite 86-94

Sprache:

Englisch

Beteiligte Personen:

Ahumada, Juan Carlos [VerfasserIn]
Alemán, Carlos [VerfasserIn]
Soto-Delgado, Jorge [VerfasserIn]
Torras, Juan [VerfasserIn]

Links:

Volltext

Themen:

Journal Article
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 17.03.2020

Date Revised 17.03.2020

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acs.jpcb.8b09549

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM291475493